He wiped his hands against his trousers and thought for a minute, then scribbled something on the list with a stub of charcoal and tossed it after the coins.

He tugged three times at the rope and the basket began a bobbing journey into the air. It rose above the lower roofs of surrounding buildings, buoyed upwards by noise. It startled the roosting jackdaws in the deserted storey and inscribed the wall with another scrawled trail among many, before it disappeared again into the window from which it had emerged.

Isaac Dan der Grimnebulin had just realized that he was dreaming. He had been aghast to find himself employed once again at the university, parading in front of a huge blackboard covered in vague representations of levers and forces and stress. Introductory Material Science. Isaac had been staring anxiously at the class when that unctuous bastard Vermishank had looked in.

“I can’t teach this class,” whispered Isaac loudly. “The market’s too loud.” He gestured at the window.

“It’s all right.” Vermishank was soothing and loathsome. “It’s time for breakfast,” he said. “That’ll take your mind off the noise.” And hearing that absurdity Isaac shed sleep with immense relief. The raucous profanity of the bazaar and the smell of cooking came with him into the day.

He lay hugely in the bed without opening his eyes. He heard Lin walk across the room and felt the slight listing of the floorboards. The garret was filled with pungent smoke. Isaac salivated.

Lin clapped twice. She knew when Isaac woke. Probably because he closed his mouth, he thought, and sniggered without opening his eyes.

“Still sleeping, shush, poor little Isaac ever so tired,” he whimpered, and snuggled down like a child. Lin clapped again, once, derisory, and walked away.

He groaned and rolled over.

“Termagant!” he moaned after her. “Shrew! Harridan! All right, all right, you win, you, you . . . uh . . . virago, you spitfire . . .” He rubbed his head and sat up, grinned sheepishly. Lin made an obscene gesture at him without turning around.

She stood with her back to him, nude at the stove, dancing back as hot drops of oil leapt from the pan. The covers slipped from the slope of Isaac’s belly. He was a dirigible, huge and taut and strong. Grey hair burst from him abundantly.

Lin was hairless. Her muscles were tight under her red skin, each distinct. She was like an anatomical atlas. Isaac studied her in cheerful lust.

His arse itched. He scratched under the blanket, rooting as shameless as a dog. Something burst under his nail, and he withdrew his hand to examine it. A tiny half-crushed grub waved helplessly on the end of his finger. It was a refflick, a harmless little khepri parasite. The thing must have been rather bewildered by my juices, Isaac thought, and flicked his finger clean.

“Refflick, Lin,” he said. “Bath time.”

Lin stamped in irritation.

New Crobuzon was a huge plague pit, a morbific city. Parasites, infection and rumour were uncontainable. A monthly chymical dip was a necessary prophylactic for the khepri, if they wanted to avoid itches and sores.